Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
651 am EDT Friday may 22 2015
a weak cold front will push southeast across the region today.
An area of high pressure will build into the Great Lakes and Ohio
Valley tonight and Saturday. The high will move east on Sunday.
Southerly flow on the back side of the high will bring warmer
temperatures for Sunday.
Near term /until 6 PM this evening/...
skies were mainly clear across the forecast area early this morning. A
weak cold front was located to our north over the southern Great
Lakes. Middle clouds associated with this feature will push into the
northern zones this morning. Radar mosaic was still indicating a few
showers with the front. However...high resolution models suggest
that most of this will fall apart by sunrise.
For later today...as the front progresses southward...daytime
heating will combine with limited moisture and weak frontal
convergence to bring clouds a perhaps a few showers over the
eastern zones. Will have to monitor if the slight chance for
showers will have to be expanded westward. This will depend on
the amount of frontal convergence and instability that can be
realized. Highs will range from the upper 60s north to the lower
Short term /6 PM this evening through Sunday night/...
weak cold front will drop south of the Ohio River this evening.
Any lingering shower activity over the southeast County warning forecast area should dissipate
after sunset. Otherwise...surface high pressure will build into
the region from the northeast. A mix of some middle and high clouds
will occur overnight as a sheared out shortwave moves across the region.
Lows will range from the upper 30s northeast to the lower 50s
Have used a blend of the 00z NAM and 00z European model (ecmwf) for the remainder
of the short term forecast. Upper level flow will undergo
amplification Saturday into Sunday as upper level ridging builds
northward into the Ohio Valley ahead of an upper level closed low
pushing into the plains. As this occurs...surface high pressure to
our east will move east through the period. Low level flow will
eventually veer to a southerly direction by Sunday. Some middle and
high level clouds will increase late Saturday and will continue
into Sunday. It now appears that the threat for showers/storms
will be delayed to perhaps late Sunday night or Monday as upper
high to our southeast keeps precipitation to our west/northwest. Temperatures
will begin a warming trend with lower to middle 70s expected on
Saturday and upper 70s to lower 80s on Sunday.
Long term /Monday through Thursday/...
a more unsettled pattern will be in place for Monday through
Thursday with shower and thunderstorm chances each day. High
temperatures will generally be in the 80s each day with low
temperatures in the 60s.
Aviation /12z Friday through Tuesday/...
VFR conditions remain across the taf sites as of 11z. Cold front
and attendant scattered-broken band of VFR ceilings oriented across northestern ind
into Northern Ohio and sagging southeast. Expect bulk of these VFR ceilings
and dying showers to move North/East of cmh/lck taf sites this
morning. Front slows as it enters southern Ohio with veering weak
flow increasing a bit ahead of the front...with some gusts this
afternoon around 17-18kt. Cumulus should develop along/ahead of
the front with a few showers possibly developing south of Columbus
down into scntl Ohio...perhaps as far back as Wilmington where a
vcsh was included in this forecast.
Front clears all taf sites by early evening with winds turning
quickly north and then northeast as high pressure builds in. Aside
from some scattered-broken cirrus...expect no restrictions to ceilings/visibility
across the taf sites through the night.
Outlook...thunderstorms possible Monday into Tuesday...with MVFR